1. Technical Field
The present invention relates to a semiconductor light-emitting element.
2. Related Art
In recent years, a flip-chip bonding (FC) mount technology has been developed, in which a semiconductor light-emitting element formed on a substrate that is transparent to light emission wavelength is reversed and mounted on a circuit board (submount) or a package. The flip-chip bonding is a mounting method that extracts light mainly from a surface on a growing substrate side that is opposite to an electrode forming surface, and is also referred to as a face-down mounting. For example, in Japanese Patent Application Laid-Open Publication No. 2010-263016, there is disclosed a semiconductor light-emitting element that includes a substrate made of sapphire, and a laminated semiconductor layer including an n-type semiconductor layer, a light-emitting layer and a p-type semiconductor layer to be laminated on the substrate, and is mounted by flip-chip bonding.
Incidentally, the semiconductor light emitting element mounted by flip-chip bonding is required to have a high reflectance for outputting light from the light-emitting layer in the direction of the substrate side to improve brightness. As a metal having high reflectivity, silver (Ag) is used.
However, silver (Ag) has high migration properties compared to other elements, and therefore, for example, defects due to a GaN potential is affected and a leakage current occurs in some cases. In addition, for preventing the migration phenomenon, for example, a method of providing a barrier layer to a metal reflection film containing silver (Ag) or the like can be considered; however, a problem of complicating manufacturing processes or the like is further generated.
An object of the present invention is to improve reliability of a metal reflection film in the FC (flip-chip bonding) mounting technology for a semiconductor light-emitting element.